U.S. patent number 11,278,277 [Application Number 16/250,869] was granted by the patent office on 2022-03-22 for bone clip with resilient arm for proximal compression.
This patent grant is currently assigned to Acumed LLC. The grantee listed for this patent is Acumed LLC. Invention is credited to Andrew W. Seykora, Matthew C. Sucec, Brandon Wedam.
United States Patent |
11,278,277 |
Seykora , et al. |
March 22, 2022 |
Bone clip with resilient arm for proximal compression
Abstract
Devices and methods for stabilizing bone. The devices and
methods may provide a more balanced proximal and distal compression
when stabilizing bone. An exemplary device may comprise a staple
member including a bridge connecting a first leg to a second leg.
The device also may comprise a resilient arm elongated between a
fixed end and a free end, and projecting from the first leg and/or
from an end region of the bridge adjoining the first leg. At least
a portion of the resilient arm intermediate the fixed and free ends
may be inwardly adjacent and spaced from an upper region of the
first leg.
Inventors: |
Seykora; Andrew W. (Portland,
OR), Sucec; Matthew C. (Portland, OR), Wedam; Brandon
(Hillsboro, OR) |
Applicant: |
Name |
City |
State |
Country |
Type |
Acumed LLC |
Hillsboro |
OR |
US |
|
|
Assignee: |
Acumed LLC (Hillsboro,
OR)
|
Family
ID: |
1000006188585 |
Appl.
No.: |
16/250,869 |
Filed: |
January 17, 2019 |
Prior Publication Data
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Document
Identifier |
Publication Date |
|
US 20200229813 A1 |
Jul 23, 2020 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61B
17/0642 (20130101); A61B 17/0682 (20130101); A61B
2017/0645 (20130101); A61B 2017/00867 (20130101); A61B
17/10 (20130101); A61B 17/8004 (20130101); A61B
2017/0641 (20130101) |
Current International
Class: |
A61B
17/064 (20060101); A61B 17/068 (20060101); A61B
17/00 (20060101); A61B 17/80 (20060101); A61B
17/10 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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2017003743 |
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Jan 2017 |
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WO |
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2017139315 |
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Aug 2017 |
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WO |
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Other References
International Search Report corresponding to related International
Patent Application No. PCT/US2020/013568 dated Apr. 21, 2020, 2
pages. cited by applicant .
International Written Opinion corresponding to related
International Patent Application No. PCT/US2020/013568 dated Apr.
21, 2020, 5 pages. cited by applicant .
International Preliminary Report corresponding to related
International Patent Application No. PCT/US2020/013568 dated Jul.
29, 2021, 7 pages. cited by applicant.
|
Primary Examiner: Lawson; Matthew J
Assistant Examiner: Nguyen; Lisa
Attorney, Agent or Firm: K&L Gates LLP
Claims
We claim:
1. A device for stabilizing a first bone part and a second bone
part, comprising: a staple member including a bridge connecting a
first leg to a second leg; a first resilient arm elongated between
a first fixed end and a first free end, the first fixed end
projecting from the first leg and/or from an end region of the
bridge adjoining the first leg, wherein at least a portion of the
first resilient arm intermediate the first fixed and first free
ends is inwardly adjacent to an upper region of the first leg,
wherein there is an absence of material between the at least a
portion of the first resilient arm and the first leg, and wherein
the first resilient arm is configured to elastically deform
towards, and relative to, the first leg; and a second resilient arm
elongated between a second fixed end and a second free end, the
second fixed end projecting from the second leg and/or from an end
region of the bridge adjoining the second leg, wherein the second
resilient arm is configured to elastically deform towards, and
relative to, the second leg, wherein the first resilient arm is
positioned with respect to the first leg and the second resilient
arm is positioned with respect to the second leg such that, while
the device is being installed in the first and second bone parts,
the first resilient arm and the second resilient arm apply a
compressive force to the first and second bone parts thereby
closing a gap between the first and second bone parts.
2. The device of claim 1, wherein the staple member has a stressed
configuration in which the first and second legs are parallel to
one another, and in which a minimum distance between the resilient
arm and a plane centered between the first leg and the second leg
is less than a minimum distance between the first leg and the
plane.
3. The device of claim 2, wherein the resilient arm and the first
leg collectively have a maximum width, and wherein the resilient
arm is configured to be elastically deformable to reduce the
maximum width while the staple member remains in the stressed
configuration.
4. The device of claim 1, wherein a separation distance between a
portion of the resilient arm and the upper region of the first leg
is configured to decrease by elastic deformation of the resilient
arm when the device is installed in bone.
5. The device of claim 1, wherein the fixed end of the resilient
arm is farther than the free end from the bridge.
6. The device of claim 1, wherein the staple member has a relaxed
configuration, and wherein the first and second legs extend
convergently from the bridge along their respective longitudinal
axes in the relaxed configuration.
7. The device of claim 1, wherein the device has a relaxed
configuration, wherein a line intersects the fixed end and the free
end of the resilient arm, and wherein the line is within 30 degrees
of parallel to a longitudinal axis of the first leg when the device
is in the relaxed configuration.
8. The device of claim 1, wherein one of the fixed and free ends of
the resilient arm is an upper end and the other of the fixed and
free ends of the resilient arm is a lower end, and wherein the
first leg and the resilient arm have a collective width measured
from an outer side of the first leg to an inner side of the
resilient arm, and wherein the collective width tapers away from
the bridge near the lower end of the resilient arm when the device
is in a relaxed configuration.
9. The device of claim 1, wherein the resilient arm is spaced from
the staple member along an entire length of the resilient arm,
except at the fixed end, when the device is in a relaxed
configuration.
10. The device of claim 1, wherein the resilient arm has a curved
longitudinal axis.
11. The device of claim 1, wherein the staple member has a stressed
configuration in which the first and second legs are parallel to
one another, and in which a minimum distance between the first
resilient arm and the second resilient arm is less than a minimum
distance between the first leg and the second leg.
12. The device of claim 11, wherein the first resilient arm and the
second resilient arm are configured to deform elastically to
increase the minimum distance between the first resilient arm and
the second resilient arm while the staple member remains in the
stressed configuration.
13. The device of claim 1, wherein the device is composed of a
nickel titanium alloy.
14. The device of claim 1, wherein the staple member defines a
plane, and wherein the staple member and the resilient arm have the
same thickness as one another orthogonal to the plane.
15. The device of claim 1, wherein the staple member and the
resilient arm are formed integrally with one another.
16. The device of claim 1, wherein the device is only one discrete
piece.
17. The device of claim 1, wherein the staple member has at least
three legs connected to one another by the bridge.
18. The device of claim 1, wherein the first leg is located in a
hole formed in the first bone part and the second leg is located in
a hole formed in the second bone part while the device is being
installed in bone.
19. A method of stabilizing bone using the device of claim 1, the
method comprising: selecting the device of claim 1; drilling a
first hole in the first bone part and a second hole in the second
bone part; and inserting the first leg and the first resilient arm
into the first hole, and the second leg and the second resilient
arm into the second hole.
20. The device of claim 1, wherein a single bone includes the first
bone part and the second bone part such that the gap is a fracture,
cut, or structural weakness in the single bone between the first
bone part and the second bone part.
21. The device of claim 1, wherein the first bone part is a first
discrete bone and the second bone part is a second discrete bone.
Description
INTRODUCTION
A bone clip, also called a bone staple, is a fastener for
stabilizing bone. The clip may be installed in one or more bones to
span a discontinuity in the bone(s), such as a fracture, a cut, or
an anatomical joint. Once installed, the clip applies compression
across the discontinuity, to encourage healing and/or fusion.
An exemplary bone clip 20 representing the prior art is shown in
FIGS. 1 and 2, respectively during and after insertion into a bone
22. The bone has a fracture 24 that creates bone fragments 26, 28.
Clip 20 has a pair of serrated legs 30 connected to one another
with a bridge 32. Legs 30 extend along convergent paths from bridge
32 when clip 20 is in an undeformed, relaxed configuration (not
shown). Clip 20 is composed of an elastically deformable material,
which allows the clip to be placed and held temporarily in a
stressed configuration with an insertion tool 34. For example, tool
34 may have upper and lower jaws 36, 38 that apply a bending moment
to bridge 32, which reorients legs 30 to be substantially parallel
to another in the stressed configuration shown in FIG. 1. Tool 34
maintains clip 20 in the stressed configuration while legs 30 are
being inserted, indicated at 40, into parallel, pre-drilled holes
42 in fragments 26, 28.
FIG. 2 shows clip 20 after legs 30 have been fully inserted into
holes 42, and insertion tool 34 has been removed. Clip 20 acts as a
spring clamp, with legs 30 as jaws. The legs urge bone fragments
26, 28 toward one another as energy stored in the stressed
configuration of clip 20 is released, to apply compression across
fracture 24. However, this design does not apply compression
uniformly along fracture 24. Instead, as shown in FIG. 2, the
amount of compression is related to the distance from bridge 32,
with distal compression 44 between the free ends of legs 30 being
significantly greater than proximal compression 46. This difference
in compressive force is indicated by force arrows of different size
and a residual gap proximally at the fracture site. An improved
bone clip is needed.
SUMMARY
The present disclosure provides devices and methods for stabilizing
bone. The devices and methods may provide a more balanced proximal
and distal compression when stabilizing bone. An exemplary device
may comprise a staple member including a bridge connecting a first
leg to a second leg. The device also may comprise a resilient arm
elongated between a fixed end and a free end, and projecting from
the first leg and/or from an end region of the bridge adjoining the
first leg. At least a portion of the resilient arm intermediate the
fixed and free ends may be inwardly adjacent and spaced from an
upper region of the first leg.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a fragmentary, sectional view of a fractured bone taken
during installation of a bone clip representing the prior art, with
legs of the bone clip being advanced into pre-drilled holes in the
bone, and with the bone clip held in an elastically deformed,
stressed configuration by an exemplary insertion tool.
FIG. 2 is a fragmentary, sectional view of the fractured bone of
FIG. 1 taken after installation of the bone clip has been completed
and showing uneven compression along the fracture of the bone.
FIG. 3 is a front view of an exemplary bone clip in a relaxed
configuration, with the bone clip having a pair of resilient arms
projecting from respective legs and configured to provide more
balanced compression of bone.
FIG. 3A is an isometric view of the bone clip of FIG. 3.
FIG. 4 is a front view of the bone clip of FIG. 3 being held in an
elastically deformed configuration by an exemplary insertion tool
(shown as fragmentary).
FIGS. 5-8 are a series of sectional, fragmentary views of the
fractured bone of FIG. 1 each taken during (FIGS. 5-7) or after
(FIG. 8) installation of the bone clip of FIGS. 3, 3A, and 4 using
the insertion tool of FIG. 4.
FIG. 9 is a fragmentary, sectional view of a fractured bone taken
after installation of the bone clip of FIGS. 3, 3A, and 4 in
different holes than in FIGS. 5-8.
FIG. 10 is a fragmentary front view of an exemplary bone clip
having a resilient arm that projects away from the bridge of the
bone clip.
FIG. 11 is a fragmentary front view of an exemplary bone clip
having a spring member that is fixed at both ends.
FIG. 12 is a fragmentary front view of an exemplary bone clip
having a pair of resilient arms associated with the same leg.
FIG. 13 is a fragmentary isometric view of another exemplary bone
clip having a pair of resilient arms associated with the same
leg.
FIG. 14 is a fragmentary isometric view of an exemplary bone clip
having a resilient arm that projects from a slot defined by an
associated leg.
FIG. 15 is an isometric view of an exemplary bone clip having four
coplanar legs each associated with a resilient arm.
FIG. 16 is an isometric view of an exemplary bone clip having a
triangular arrangement of three legs each associated with a
resilient arm.
FIG. 17 is an isometric view of an exemplary bone clip having a
rectangular arrangement of four legs each associated with a
resilient arm.
FIG. 18 is an isometric view of an exemplary multi-piece bone clip
having a pair of hinged elongate members.
FIG. 19 is a front view of an exemplary bone clip arranged in a
stressed configuration (i.e., with its legs parallel to one
another) and having a pair of resilient arms and a slanted
bridge.
FIG. 20 is a front view of an exemplary bone clip arranged in a
stressed configuration (i.e., with its legs parallel to one
another) and having a pair of resilient arms and a stepped
bridge.
DETAILED DESCRIPTION
The present disclosure provides devices and methods for stabilizing
bone. The devices and methods may provide a more balanced proximal
and distal compression when stabilizing bone. An exemplary device
may comprise a staple member including a bridge connecting a first
leg to a second leg. The device also may comprise a resilient arm
elongated between a fixed end and a free end, and projecting from
the first leg and/or from an end region of the bridge adjoining the
first leg. At least a portion of the resilient arm intermediate the
fixed and free ends may be inwardly adjacent and spaced from an
upper region of the first leg.
Another exemplary device for stabilizing bone is provided. The
device may comprise a staple member including a bridge connecting a
first leg to a second leg. The device also may comprise an arm
inwardly adjacent and pivotally connected to an upper region of the
first leg. The arm may be firmly attached to a lower region of the
first leg.
An exemplary method for stabilizing bone with the device is
provided. In the method, a first hole and a second hole are drilled
in bone. The first leg and the arm of the device may be inserted
into the first hole, and the second leg of the device may be
inserted into the second hole.
Further aspects of the present disclosure are described in the
following sections: (I) overview of bone clips for proximal
compression, (II) methods of stabilizing bone with bone clips, and
(III) examples.
I. OVERVIEW OF BONE CLIPS FOR PROXIMAL COMPRESSION
This section provides an overview of bone clips that provide
proximal compression using at least one spring member and/or arm,
as exemplified by bone clip 50; see FIGS. 3, 3A, and 4.
Bone clip 50 is shown in a relaxed configuration in FIGS. 3 and 3A,
and in a stressed configuration in FIG. 4. Clip 50 includes a
staple member 52 having a bridge 54 joined to and interconnecting a
pair of legs 56. Each leg 56 has an upper end 58 (interchangeably
called a proximal end) that forms a junction with bridge 54, and a
lower end 60 (interchangeably called a distal end) that is farthest
from bridge 54. The terms "upper" and "lower," and "proximal" and
"distal," are defined by relative proximity to bridge 54, with
upper and proximal being closer to the bridge than lower and
distal. The terms "inner" and "outer" are respectively closer to
and farther from a central plane and/or central axis, as defined
below. In other embodiments, bone clip 50 may have at least three
or at least four legs 56 (e.g., see Example 2 of Section III).
A spring member 62 may be associated with at least one leg 56, or
respective spring members 62 may be associated with at least two
legs, such as each leg 56 as in the depicted embodiment. More
specifically, each spring member 62 may project from one of legs 56
and/or from an end region of bridge 54 adjoining the leg. In the
depicted embodiment, each spring member 62 is an arm 64 that
projects proximally from leg 56 and has a distal fixed end 66 and a
proximal free end 68. Arm 64 may be described as a resilient arm
(i.e., the arm is elastically deformable, which allows the arm to
function as a spring, such as a cantilever spring). In other
embodiments, fixed end 66 is proximal and free end 68 is distal,
both ends of spring member 62 are fixed ends, and/or spring member
62 includes a pair of resilient arms 64 associated with one of legs
56 (see Example 1 of Section III). In other embodiments, the bone
clip includes a plurality of discrete pieces that are pivotably
connected to one another (see Example 3 of Section III).
Spring member 62 and/or arm 64 may have any suitable properties. At
least a portion 70 of spring member 62 and/or arm 64 intermediate
its ends may be located inwardly adjacent and spaced from an upper
region 72 of associated leg 56. The term "inward" as used herein
means at least generally toward a different leg(s) 56 of bone clip
50, and/or at least generally toward a central plane 74 (and/or a
central axis 75) that intersects bridge 54 and is centered between
legs 56. The terms "inner" and "outer" are respectively closer to
and farther from central plane 74 or axis 75. For example, in the
depicted embodiment, each leg 56 has a serrated inner side and a
smooth outer side.
Portion 70 (and/or free end 68) may be spaced from upper region 72
of associated leg 56 by any suitable distance, such as less than
about 25%, 20%, or 15% of the maximum distance between legs 56,
and/or more than about 2%, 3%, 4% or 5% of this maximum distance. A
larger spacing may be preferable in some cases, in order to
maintain compression dynamically as bone is resorbed from the
interface between bone fragments and/or bones.
The spring member and/or arm may be elongated between ends thereof
to define a longitudinal axis, which may be linear or curved, among
others. The curvature may, for example, be convex with respect to
central plane 74 and/or axis 75, as in the depicted embodiment. A
curved longitudinal axis may be preferred in some cases, as it may
offer the spring member and/or arm two distinct spring constants,
namely, a first spring constant for closing the gap, if any,
between free end 68 and upper region 72, and a second spring
constant for reducing the curvature, if any, of the spring member
and/or arm.
Legs 56 may extend convergently from bridge 54 when bone clip 50 is
in a relaxed configuration, as shown in FIGS. 3 and 3A. In other
words, upper ends 58 of legs 56 may be significantly farther from
one another than lower ends 60 are to one another. Each leg may
form any suitable angle with a respective plane that is parallel to
central plane 74 (and/or with a respective axis that is parallel to
central axis 75), such as at least about 5 or 10 degrees, and/or
about 5-25 degrees or 10-20 degrees, among others. Legs 56 may form
angles of the same size with the planes and/or axes.
Legs 56 may be substantially parallel to one another, as in FIG. 4,
when bone clip 50 is being held in a stressed configuration by an
insertion tool 34, before or during insertion into bone. Insertion
tool 34 may engage only bridge 54 of bone clip 50 (as in FIG. 1) to
apply deforming stress. In other embodiments, insertion tool 34 may
engage bridge 54 and legs 56, or legs 56 alone, of the bone
clip.
In some embodiments, bone clip 50 may have one or more protrusions,
such as tabs 76, to facilitate operative engagement of insertion
tool 34 with bone clip 50. Each protrusion may project from any
suitable position of staple member 52, such as the top side of
bridge 54, as shown here, longitudinally from bridge 54 at an end
thereof, the front and/or back side of bridge 54, the bottom side
of bridge 54, and/or one of legs 56. Each protrusion may be
configured to be detached from staple member 52, such as by
breaking off or cutting the protrusion from the staple member, or
the protrusion may be sized and positioned to remain attached to
staple member 52 after bone clip 50 has been implanted in a
subject.
Insertion tool 34 may deform bridge 54 by applying a bending moment
to staple member 52. Bridge 54 may be bowed upward (or straight) in
the relaxed configuration of staple member 52, as shown in FIG. 3,
and may be less curved and/or bowed downward in the stressed
configuration of staple member 52, as shown in FIG. 4. Insertion
tool 34 may create the bending moment by applying downward stress
centrally along bridge 54, and upward stress closer to the ends of
bridge 54. For example, in the depicted embodiment, insertion tool
34 has a pair of limbs 78 with respective cutouts 80 that mate with
tabs 76. Limbs 78 then are rotated toward one another, which causes
a toe 82 of each limb 78 to press downward on a central region of
bridge 54, while a wall of each cutout 80 pulls upward on one of
tabs 76. Limbs 78 then may be locked to one another, to maintain
bone clip 50 in the stressed configuration of FIG. 4 until legs 56
have been inserted into bone.
Each arm 64 may be closer than its associated leg 56 to central
plane 74 and/or axis 75 when bone clip 50 is in the stressed
configuration of FIG. 4. In other words, a minimum distance 84
between arm 64 and plane 74 and/or axis 75 may be less than a
minimum distance 86 between leg 56 and plane 74 and/or axis 75.
Insertion of bone clip 50 into bone, while the bone clip is held in
the stressed configuration of FIG. 4, may increase distance 84 by
elastically deforming at least one arm 64, as described further
below.
The bone clips of the present disclosure may have any suitable
construction and composition. Each bone clip may be formed as only
one piece (i.e., a unitary construction), as in FIG. 3, or may
include two or more discrete pieces that are movably connected to
one another (e.g., see Example 3 of Section III). Any combination
of bridge 54, legs 56, spring member(s) 62 (and/or arm(s) 64), and
tabs 76 (if any) may be formed integrally with one another. The
bone clip may be formed of any suitable biocompatible material,
such as metal (stainless steel, titanium, titanium alloy, cobalt
chrome, magnesium, magnesium alloy, etc.), polymer, or the like. In
some embodiments, the bone clip may be composed of nickel titanium,
also known as Nitinol, which is an alloy of nickel and titanium,
generally in roughly equal amounts. Nickel titanium may be
described as a shape memory alloy.
Bone clip 50 may have a uniform thickness measured between a front
side 88 and a back side 90 (see FIG. 3A). Sides 88, 90 may be
substantially planar surfaces that are parallel to one another.
Accordingly, the bone clip may be manufactured by cutting the clip
from a flat plate. The thickness of bone clip 50 may be greater
than, about the same as, or less than, the average width of bridge
54 and/or each leg 56 (measured in a plane defined the bridge and
legs). For example, the thickness may be at least about 25% of the
average width of the bridge and/or each leg.
Further aspects of bone clip 50 that may be suitable are described
elsewhere herein, such as in Sections II and III.
II. METHODS OF STABILIZING BONE WITH BONE CLIPS
This section describes exemplary methods of stabilizing bone with
the bone clips of the present disclosure, as exemplified with bone
clip 50 of FIGS. 3, 3A, and 4 having two legs 56 each associated
with a resilient arm 64; see FIGS. 4-9. The steps described here
can be performed in any suitable order and combination using any of
the bone clips of the present disclosure.
Bone to be stabilized may be selected. The bone may be a single
bone 22 or at least a pair of adjacent bones (e.g., to be fused to
one another). If a single bone, the bone may have a fracture 24 (as
shown in FIG. 5), a cut (for an osteotomy), a structural weakness,
or the like. Exemplary bones that may be suitable include long
bones of the arm (humerus, ulna, and/or radius), bones of the hand
(carpals, metacarpals, and/or phalanges), long bones of the leg
(femur, tibia, and/or fibula), bones of the foot (talus, calcaneus,
tarsals, metatarsals, and/or phalanges), the pelvis, ribs, the
sternum, vertebrae, clavicles, scapulas, or the like. The bone may
be stabilized temporarily by the bone clip, only during a surgical
procedure, or more permanently for any suitable amount of time
after the bone clip has been implanted in a subject. Accordingly,
the bone clip may be used for fracture fixation, osteotomy
fixation, fusion of bones of an anatomical joint, temporary
reduction, or the like.
A bone clip may be selected for stabilizing the bone. The bone clip
may have two legs, or three or more legs. The size of the bone clip
may be chosen according to the size of bone to be stabilized and
the magnitude of loads to be exerted on the bone once
stabilized.
Holes 42 may be drilled in the selected bone. A separate hole 42
may be drilled to receive each leg 56 of bone clip 50. Each hole
may be slightly deeper than the length of leg 56 to be received.
The holes may be positioned such that a discontinuity in the
selected bone (e.g., fracture 24) is intermediate a pair of legs 56
of the clip. Each hole 42 may be drilled generally normal to the
local exterior surface of the selected bone, and the holes may be
drilled parallel to one another. The holes may be drilled after
pieces of bone are aligned and surfaces thereof (e.g., fracture or
cut surfaces 92, 94) are approximated, although a small gap 96
between fragments 26, 28 may be present. Holes 42 may be spaced
from one another such that a minimum distance 98 between the holes
substantially matches a minimum distance 100 between legs 56. A
minimum distance 102 between arms 64 is generally less than
distance 98 (and distance 100). Each hole 42 may have a diameter
D.sub.1, and bone clip 50 may define a collective, relaxed maximum
width D.sub.2 of the corresponding leg 56 and arm 64, measured in a
plane defined by the bone clip. Generally,
D.sub.1.gtoreq.D.sub.2.
Bone clip 50 may be deformed to a stressed configuration with
insertion tool 34. The insertion tool may hold the bone clip in the
stressed configuration until legs 56 of bone clip 50 are
substantially fully inserted into respective holes 42, as shown in
FIGS. 6 and 7. As shown in FIG. 7, the process of insertion may
cause arms 64 to move farther apart from one another by deformation
(to increase distance 102 relative to FIG. 5). Since a small gap 96
between bone fragments or bones may be present at the start of
insertion, bone fragments 26, 28 also may be moved closer together
(to decrease distance 98 proximally (see FIG. 5)). This movement
may be produced by force exerted on the near sides 104 of holes 42
by arms 64 as the proximal portions of legs 56 and their adjacent
arms 64 are inserted into holes 42 (see FIG. 7). The gap, if any,
between bone fragments 26, 28 may be closed only proximally, in
response to proximal compression 106 applied by arms 64. The arms
may be compressed toward their associated legs 56 by contact with
near side 104 of each hole 42. As a result, the collective width
corresponding to D.sub.2 may be reduced (also see FIG. 5).
FIG. 8 shows bone clip 50 in a fully installed configuration.
Insertion tool 34 has been removed, and tabs 76 have been detached
from bridge 54. Legs 56 have moved closer to one another, to
decrease distance 100, which results in distal compression 107.
Compression may be more uniform along fracture 24 than with bone
clips of the prior art (e.g., see FIGS. 1 and 2). Furthermore, bone
clip 50 can continue to apply proximal and distal compression 106,
107 if bone resorption occurs around fracture 24 during healing.
This resorption may further decrease distance 98 (also see FIG. 5),
as arms 64 expand inward from legs 56 to apply proximal compression
dynamically. (This expansion increases the collective width
measured between the outer side of leg 56 and the inner side of
corresponding arm 64.) The outer sides of legs 56 do not contact
the far sides 108 of holes 42, even if arms 64 return to their
relaxed configurations, when D.sub.1>D.sub.2.
FIG. 9 shows bone clip 50 installed in holes 42 that have been
widened proximally, but selectively at far sides thereof, indicated
at 110. This widening may be performed with a punch, before or
after bone clip 50 has been installed. The use of a punch or
similar tool allows distance 98 to remain the same, while
increasing the diameter of hole 42 proximally to accommodate a
greater amount of bone resorption (and thus a greater distance of
travel of the bone fragments toward one another). Accordingly, a
smaller total volume of bone can be removed relative to drilling
wider holes 42 at the outset.
III. EXAMPLES
This section describes selected embodiments of bone clips for
stabilizing bone and methods of using the bone clips to stabilize
bone. Any of the features of the devices and methods described in
this section may be combined with one another and with any of the
features described elsewhere in the present disclosure, in any
suitable combination. These embodiments are intended for
illustration and should not limit the entire scope of the present
disclosure.
Example 1. Spring Member Configurations
This example describes exemplary alternative spring member
configurations for incorporation into bone clip 50 of FIGS. 3, 3A,
and 4-9; see FIGS. 10-14. Only one leg 56 and an end region of
bridge 54 are shown for each embodiment. Each other leg 56 of the
clip may (or may not) be associated with a spring member,
optionally similar to what is shown.
FIG. 10 shows a bone clip 50 having a spring member 62 in the form
of a resilient arm 64 projecting distally from bridge 54. A fixed
end 66 of arm 64 is located at the junction between bridge 54 and
leg 56, and a free end 68 of the arm is located distally therefrom,
closer to lower end 60 of leg 56.
FIG. 11 shows a bone clip 50 having a spring member 62 with no free
end.
Instead, both ends are fixed to staple member 52.
FIG. 12 shows a bone clip 50 having a spring member 62 formed by a
pair of resilient arms 64a, 64b. Each arm 64a, 64b has a fixed end
66 and a free end 68. Arm 64a projects distally from bridge 54, and
arm 64b projects proximally from leg 56.
FIG. 13 shows a bone clip 50 having a pair of resilient arms 64a,
64b each extending proximally from leg 56 to a free end 68 that is
closer to bridge 54. The arms are attached to front side 88 and
back side 90, respectively, of leg 56, and may be offset
transversely from staple member 52.
FIG. 14 shows a bone clip 50 having a resilient arm 64 projecting
proximally from a slot 112 defined by a leg 56. Slot 112 may be
sized to permit at least part of arm 64 to move into the slot as
the arm is deformed.
Example 2. Bone Clips with at Least Three Legs
This example describes exemplary bone clips 50 having at least
three legs and including a spring member and/or resilient arm to
apply proximal compression to bone; see FIGS. 15-17.
FIG. 15 shows a bone clip 50 having four coplanar legs 56 each
associated with a respective resilient arm 64. In other
embodiments, only a subset of legs 56 are associated with a
resilient arm 64.
FIG. 16 shows a bone clip 50 having a triangular arrangement of
three legs 56 each associated with a resilient arm 64. In other
embodiments, only a subset of legs 56 are associated with a
resilient arm 64.
FIG. 17 shows a bone clip 50 having a rectangular arrangement of
four legs 56 each associated with a resilient arm 64. In other
embodiments, only a subset of legs 56 are associated with a
resilient arm 64.
Example 3. Bone Clip with Pivotally Connected Members
This example describes an exemplary bone clip 120 including at
least one pivotally connected elongate member 122; see FIG. 18.
Bone clip 120 includes a staple member 52 having a bridge 54
connecting a pair of legs 56 to one another. Bridge 54 and a pair
of upper leg regions 124 are formed by a body 126, which may be
only one piece. A respective elongate member 122 is pivotally
connected at a pivotable joint 128 to a distal end of each upper
leg region 124. Elongate member 122 forms a lower leg region 130 of
one of legs 56 and also forms an arm 132. However, arm 132 may be
substantially less deformable than arm 64 of bone clip 50. Arm 132
may be firmly attached to lower leg region 130 (e.g., formed
integrally with the lower leg region), and may extend proximally
from pivotable joint 128 to a proximal end 134.
Bone clip 120 may be installed as described above in Section II for
bone clip 50. However, pivotal motion of each elongate member 122,
rather than elastic deformation of an arm with respect to an
associated leg, provides balanced proximal and distal
compression.
Example 4. Bone Clip with Resilient Arms and a Slanted or Stepped
Bridge
This example describes exemplary bone clips 50 having a slanted
bridge 54 (FIG. 19) or a stepped bridge 54 (FIG. 20) connecting a
pair of legs 56 to one another. The bone clips are shown in a
stressed configuration (e.g., similar to FIG. 4) with legs 56
parallel to one another, but, for simplification, in the absence of
an insertion tool to produce/maintain the stressed configuration.
Each bone clip 50 may have a respective spring member 62 and/or
resilient arm 64 associated with at least one leg 56 (or each leg
56 as shown). The bone clips of this example may have any suitable
combination of features described in the present disclosure.
FIG. 19 shows bridge 54 forming an angle of less than 90 degrees
with a leg 56 at one end and an angle of greater than 90 degrees
with the other leg. The angles may add up to about 180 degrees when
the bone clip is in the stressed configuration, as shown here. The
smaller angle may be less than about 85, 80, 75, 70, 65, or 60
degrees, among others, and/or greater than about 30, 40, 45, 50, or
60 degrees, among others.
FIG. 20 shows bridge 54 forming an angle of about 90 degrees with
each leg 56. However, the bridge bends abruptly intermediate the
ends thereof, to form a step, which offsets the legs relative to
another parallel to a central axis of the clip.
Example 5. Selected Embodiments
This example describes selected aspects of the present disclosure
as a series of indexed paragraphs.
Paragraph 1. A device for stabilizing bone, comprising: (a) a
staple member including a bridge connecting a first leg to a second
leg; and (b) a resilient arm elongated between a fixed end and a
free end, and projecting from the first leg and/or from an end
region of the bridge adjoining the first leg, wherein at least a
portion of the resilient arm intermediate the fixed and free ends
is inwardly adjacent and spaced from an upper region of the first
leg.
Paragraph 2. The device of paragraph 1, wherein the staple member
has a stressed configuration in which the first and second legs are
parallel to one another, and in which a minimum distance between
the resilient arm (in its relaxed configuration) and a plane
centered between the first leg and the second leg is less than a
minimum distance between the first leg and the plane.
Paragraph 3. The device of paragraph 2, wherein the resilient arm
and the first leg collectively have a maximum width, and wherein
the resilient arm is configured to be elastically deformable to
reduce the maximum width while the staple member remains in the
stressed configuration.
Paragraph 4. The device of any of paragraphs 1 to 3, wherein a
separation distance between a portion of the resilient arm and the
upper region of the first leg is configured to decrease by elastic
deformation of the resilient arm when the device is installed in
bone.
Paragraph 5. The device of any of paragraphs 1 to 4, wherein the
fixed end of the resilient arm is farther than the free end from
the bridge.
Paragraph 6. The device of any of paragraphs 1 to 5, wherein the
staple member has a relaxed configuration, and wherein the first
and second legs extend convergently from the bridge along their
respective longitudinal axes in the relaxed configuration.
Paragraph 7. The device of any of paragraphs 1 to 6, wherein the
device has a relaxed configuration, wherein a line intersects the
fixed end and the free end of the resilient arm, and wherein the
line is within about 10, 20, 25, or 30 degrees of parallel to a
longitudinal axis of the first leg when the device is in the
relaxed configuration.
Paragraph 8. The device of any of paragraphs 1 to 7, wherein one of
the fixed and free ends of the resilient arm is an upper end and
the other of the fixed and free ends of the resilient arm is a
lower end, and wherein the first leg and the resilient arm have a
collective width measured from an outer side of the first leg to an
inner side of the resilient arm, and wherein the collective width
tapers away from the bridge near the lower end of the resilient arm
when the device is in a relaxed configuration.
Paragraph 9. The device of any of paragraphs 1 to 8, wherein the
resilient arm is spaced from the staple member along an entire
length of the resilient arm, except at the fixed end, when the
device is in a relaxed configuration.
Paragraph 10. The device of any of paragraphs 1 to 9, wherein the
resilient arm has a curved longitudinal axis.
Paragraph 11. The device of any of paragraphs 1 to 10, wherein the
resilient arm is a first resilient arm, further comprising a second
resilient arm projecting from the second leg and/or from an end
region of the bridge adjoining the second leg.
Paragraph 12. The device of paragraph 11, wherein the staple member
has a stressed configuration in which the first and second legs are
parallel to one another, and in which a minimum distance between
the first resilient arm and the second resilient arm is less than a
minimum distance between the first leg and the second leg.
Paragraph 13. The device of paragraph 12, wherein the first
resilient arm and the second resilient arm are configured to deform
elastically to increase the minimum distance between the first
resilient arm and the second resilient arm while the staple member
remains in the stressed configuration.
Paragraph 14. The device of any of paragraphs 1 to 13, wherein the
device is composed of a nickel titanium alloy.
Paragraph 15. The device of any of paragraphs 1 to 14, wherein the
staple member defines a plane, and wherein the staple member and
the resilient arm have the same thickness as one another orthogonal
to the plane.
Paragraph 16. The device of any of paragraphs 1 to 15, wherein the
staple member and the resilient arm are formed integrally with one
another.
Paragraph 17. The device of any of paragraphs 1 to 16, wherein the
device is only one discrete piece.
Paragraph 18. The device of any of paragraphs 1 to 17, wherein the
staple member has at least three legs connected to one another by
the bridge.
Paragraph 19. The device of any of paragraphs 1 to 18, wherein the
device is configured to be used for cortical and/or cancellous
bone.
Paragraph 20. The device of any of paragraphs 1 to 19, (i) wherein
each leg is located in a hole formed in a bone or bone fragment,
and/or (ii) wherein a central axis is centered between the legs,
and wherein upper ends of the legs are offset relative to one
another parallel to the central axis, and/or wherein the bridge is
slanted and/or stepped to produce an offset of the upper ends of
the legs relative to one another parallel to the central axis.
Paragraph 21. A method of stabilizing bone using the device of any
of paragraphs 1 to 20, the method comprising: (i) drilling a first
hole and a second hole in bone; and (ii) inserting the first leg
and the resilient arm into the first hole, and the second leg into
the second hole.
Paragraph 22. The method of paragraph 21, wherein the step of
inserting elastically deforms the resilient arm outward.
Paragraph 23. The method of paragraph 21 or 22, wherein the step of
inserting applies proximal compression to the bone.
Paragraph 24. The method of paragraph 23, wherein the proximal
compression is applied in part by contact between the resilient arm
and the bone at the first hole.
Paragraph 25. The method of paragraph 23 or 24, wherein the device
has a pair of resilient arms, and wherein the proximal compression
is applied to the bone by the pair of resilient arms at the first
and second holes.
Paragraph 26. The method of any of paragraphs 21 to 25, further
comprising a step of applying distal compression to the bone via
contact between the first leg and the first hole and between the
second leg and the second hole.
Paragraph 27. The method of paragraph 26, wherein the step of
inserting is performed while the staple member is held in a
stressed configuration with an insertion tool, wherein the distal
ends of the first and second legs are farther apart from one
another in the stressed configuration relative to a relaxed
configuration of the staple member, and wherein the step of
applying distal compression includes a step of releasing the staple
member from the insertion tool.
Paragraph 28. The method of any of paragraphs 21 to 27, wherein the
first and second holes are formed in the same bone, and wherein the
same bone has a fracture or a cut intermediate the first and second
holes.
Paragraph 29. The method of any of paragraphs 21 to 28, wherein the
step of inserting includes a step of moving a portion of the
resilient arm closer to the first leg, and/or a step of moving bone
fragments or different bones closer to one another.
Paragraph 30. The method of any of paragraphs 21 to 29, wherein the
first and second holes have respective near sides that are closer
to one another than central axes of the holes, and wherein the step
of inserting places the resilient arm in contact with the near side
of the first hole.
Paragraph 31. The method of paragraph 30, wherein the resilient arm
is a first resilient arm, wherein the device has a second resilient
arm associated with the second leg, and wherein the step of
inserting places the second arm in contact with the near side of
the second hole.
Paragraph 32. The method of any of paragraphs 21 to 31, wherein the
first leg and the resilient arm have a collective width when the
device is in a relaxed configuration, and wherein the step of
inserting reduces the collective width.
Paragraph 33. A device for stabilizing bone, comprising: (a) a
staple member including a bridge connecting a first leg to a second
leg; and (b) an arm inwardly adjacent and pivotally connected to an
upper region of the first leg; wherein the arm is firmly attached
to a lower region of the first leg.
Paragraph 34. The device of paragraph 33, wherein the first leg has
a pivotable joint formed intermediate a proximal end and a distal
end of the first leg, and wherein the arm and the lower region of
the first leg are formed by an elongate member that is rotatable as
a unit with respect to the upper region of the first leg via the
pivotable joint.
Paragraph 35. The device of paragraph 33 or 34, wherein the arm and
the lower region of the first leg are formed integrally with one
another.
Paragraph 36. The device of any of paragraphs 33 to 35, wherein the
arm is a first arm and the elongate member is a first elongate
member, wherein a second elongate member forms a second arm and a
lower region of the second leg and is pivotable with respect to an
upper region of the second leg.
Paragraph 37. The device of any of paragraphs 33 to 36, wherein the
bridge is formed integrally with the upper region of the first leg
and with an upper region of the second leg, and wherein a
respective elongate member is pivotally connected to a distal end
of the upper region of the first leg and the upper region of the
second leg.
The disclosure set forth above may encompass multiple distinct
inventions with independent utility. Although each of these
inventions has been disclosed in its preferred form(s), the
specific embodiments thereof as disclosed and illustrated herein
are not to be considered in a limiting sense, because numerous
variations are possible. The subject matter of the inventions
includes all novel and nonobvious combinations and subcombinations
of the various elements, features, functions, and/or properties
disclosed herein. The following claims particularly point out
certain combinations and subcombinations regarded as novel and
nonobvious. Inventions embodied in other combinations and
subcombinations of features, functions, elements, and/or properties
may be claimed in applications claiming priority from this or a
related application. Such claims, whether directed to a different
invention or to the same invention, and whether broader, narrower,
equal, or different in scope to the original claims, also are
regarded as included within the subject matter of the inventions of
the present disclosure. Further, ordinal indicators, such as first,
second, or third, for identified elements are used to distinguish
between the elements, and do not indicate a particular position or
order of such elements, unless otherwise specifically stated.
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